1. Field of the Invention
This invention relates generally to a surgical cannula and more particularly to a cannula that utilizes a ball valve requiring no manual manipulation for its use.
2. Description of the Prior Art
Cannulas are hollow sleeves that are used to allow surgical instruments to be introduced into a body cavity. First, the cannula with trocar is introduced into the body (the trocar is removed) and then the surgical instruments are placed through the cannula into the body. Often, when surgery is being performed a gas is entering into the body cavity targeted for surgery so that there is room for surgical instruments to be manipulated within the cavity. Therefore, it is important that the cannula through which the surgical instruments are entered into the body cavity do not allow this gas to exit the body cavity.
It is known in the industry to use cannulas having trumpet valves incorporated therein. The trumpet valves must be manually manipulated during insertion and removal of the surgical instruments so that a seal preventing the release of gas is maintained in the cannula. The trumpet valves which must clamp around the instruments can be traumatic to the instruments themselves. Furthermore, the requirement of manual manipulation of the trumpet valve is cumbersome and inhibits focused attention being given to the manipulation of the surgical instruments themselves.